Nitrostarch explosive



PATENT OFFICE,

' UNITED STATES WALTER o. Sunni-me, or ALLENTOWN, immisvnvnnm,ns'srenon, BY MESNE ASSIGNMENTS,- TO TROJAN'POWDEB, PORATION OF NEW YORKj COMPANY, OF NEW YORK, iv. Y.,.A con nnrnosre'non nxrLosIvEj.

No Drawing.

To all whom it may concern: 7

.Be it known that I, WALTER O. SNELLING,

a citizen of the United States, andresident' an explosive which willhave great strength and at the same time be relatively insensitive toblows or friction. This combination of qualities is essential ordesirable in certain classes of military. explosives, for ex-v ample foruse as an explosive charge" in drop-bombs, and sea-mines, and for otheruses. 7

Nitro-starch is itself a powerful explosive, and its strength is notmaterially. decreased by the presence of alimited amount The water doesnot prevent detonation by an initial detonating means of suflicientstrength, and owing to the-intense heat produced at the instant'ofexplosion, the water present serves to increase the volume of gas whichis produced. The pres ence of water in sufiicient quantity to thoroughlywet thenitro-starch grains has the effect of rendering the explosiverelatively insensitive toflblo ws or friction.

As however the water will evaporate when the wet nitro-starchis exposedto the air. the properties of the explosive mixture will rapidly changeunderthe conditions ciclent to practical use. To avoid this, I- mix withthe nitro-starch and water, in suitable proportions, a substance solublein water and having sufficient affinity therefor to pre-' vent readyevaporation of the water when the mixture is exposed to the air, and Ihave discovered that in this manner highly useful explosives can beprepared having both the required strength and insensitiven'es's toblows or friction, Y

I have found both inorganic and organic substances possessingtherequired hygro scopicity for the purpose stated. Examples of inorganicsalts" are calcium chlorid and magnesium chlorid.- As howeverthese'salts are explosively inert, and to obtain maximum strength it isdesirable that no .inert material shouldbe present, I prefer'to use asalt which is not only highly deliquescent, but which through itsdecomposition upondetonation of the mixture, adds .to the Specificationof Letters Patent.

Application filed October a, 1918.. Serial No. gsavsl Y Patented Aug.2,1921.

v, strength of theexplosive. As active inorganie agents, Iinstancethenitrates of am mon1um, calcium, iron and lithium, which are highlyhygroscopic" and particularly well adapted to the purpose of my inventlon. Ammonium nitrate is the salt: preferred.

Of organic materials suitable to the prajct1ce of my invention, dextroseand levulose have been found to .be quite satisfactory, either alone oradmixed-1 Ordinary invert sugar serves very well, and commercial glucoseis satisfactory, Other organic'materials possessin may be employed,

By varying the proportions of'the several ingredients referred to, thephysical char-v actertstics of the explosive (32111136 regulated asdesired, to suit different purposes. For example, with v a mixturecontaining 50% 'nitro-starch, the deliquescent ingredient, say ammoniumnitrate may represent 40% and the "water 10%. This mixture is softandplastic. A mixture containing50% nitroestarch, 45% ammonium nitrateand nitrate, and 13%- consistency. r

f With mixtures containing a higher percentage-of nitro-starch, as fromto 75%, the ammonium nitrate and-water will represent from 40% to 25%,and of the :soluti0n 0f ammonium nitrate in water, less tl1anl,65 shouldbe ammonium nitrate. such mixture the percentage of Water is ofwater, isof semi-fluid preferably more than 10% ofthe entire mixtemperaturethewater' will nothold insm lution more than approximately double its105 weight of ammoniumnitrate, it willbe ap I parent that in some oftheexamples given the water willnot be suflicient to hold in solution theentire amount of deliquescent salt-present, but as'in'any event thewater 1 10 9; sufficient hydroscopicity of water, is quite while one con7 taming 50% nit-ro-starch, 37% ammonium present Willbe in excess of 5%of thetotal mixture,'it Will be sufiicient to hold in solution asubstantial amount of thedeliques cent salt.

The proportions given for ammonium ni- V trate apply substantially withother hygro scopic ingredients employed for the same purpose, includingnamed. V V

In the preparation of nitro starch explosives according tomy invention,I may. directly mix together the three constituents in suitableproportions, using any type of mixer which will insure thoroughincorporation, or I may add together the Water and the water solubleingredient to obtaina concentrated solution, and this solution may thenbe 'added to the nitro-starch With properincorporation. -t i It will beunderstood thatinstead'of a sink gle deliquescent material, I can use acombination of such materials. For example, the deliquescence, ofammonium nitrate can be increased by the addition thereto of a. smallamount-say 1%--of a related .deliquescent salt, such as lithium nitrateor sodium'nitrate. k i I It Will also be understood thatin' utilizingthe explosive described, it can be incorporated with a suitablecarbonaceous or, combustible ingredient, in accordance with the practicein. this art. e

A characteristic of explosives made in accordance- With my invention istheir great strength, particularly their exceptional shatv teringstrength and their relativelygreat insensitiveness. Theirinsensitivenessis due; to the fact that the nitro-starch grains arethoroughly wet with the solution of the deliquescent material in Water,andtheaction of the deliquescent material prevents the ready evaporationof the Water from any exposed surface of the material. The exceptionalstrength which these explosives show is due to the fact thatnitro-starch is capable of detonating, even ,in the Wet condition, thatthis nitro-starch is.capable of bringing about the simultaneousdetonation of the wet ammo nium nitrate-in those explosives in whichammoniumnit-rate is the deliquescent agent used, and that even thewaterwhich. is pres.- entin'the mixture causes an increased gas volume at themoment of detonation owing to-the intense heat producedat the time ofexplosion, all of the constituents thus assisting in the production ofavery great gas volume at the moment of explosion. V V

AlthoughI have described certain specific mixtures of nitro -starch,ater and Water soluble materials having afiinity for'water, I

, do not Wish in the broader .aspect of theinvention, to be limited tothehygroscopic materials specified, nor proportions named, since myinvention is broadly applicable tovexplosives containing nitro-starch, adeliquescent soluble material.

those herein specifically insuch amount-as to becapableot'holding insolution-a substantial amount of the Water ,I la I deliquescent salt,and sufiicient Water to hold in solution a substantial amount of thedeliquescent salt.

- 2. A nitrostarch' explosive comprising nitro-starch mainta ned inWet-condition by theadditlon ,of rvater containlng a dissolved salthaving great afiinity. for Water.

A ,nitro-starch explosive containing Water, and an ingredient havingsuflicient afiinity for. Water to prevent itsready evaporation throughexposure to air.

4i. nitro-starch"explosivecontaining a saturated solution of adeliquescent salt;

- 5, .A nitro-starch explosive I comprising 50% of nitroEstarch, i0% ofammonium nitrate and 10%: of Water.

. 6. A nitro-starch'explosive comprising nitro-starch, a. deliquescentnitrate, suflicient Water to hold a substantial amount of thedeliquescentnitratein solution, and a suitable carbonaceous orcombustible ingredient.

.7. A nitro-starch explosive comprising nitro-starch, a .saturatedsolution of-an inorganic nitrate, and-combustible constituent.

8; An explosive consisting of n1tro-starch contalning Water suf icientto render it saie in handling,,bntinsufiicien'tto prevent itsdetonation,substantially as described.

. 9. An explosive consisting of nitro-starch containing a substantialpercentage of Water and, ammonium nitrate, substantially as dc scribed.0, 10. An explosive consisting of nitro-starch than 10%; ofammoniumnitrate, substantially as described. I 11. An explosive consisting ofnitro-starch containing more than 10% ofwater and more than. 10% ofammonium nitrate, substantially asdescribed.

12. An explosive consisting of approximately50% ofnitro-starch, morethan 10% ammonium nitrate, and approximately 15% of Water. .7 7. l3.Anexplosive consisting of 60% to 375% offnitro-starch and from 25% to40% of a solution of ammonium nitrate in Water, substantially asdescribed. 0 a i 14. An I explosive consisting of 60% to 75.ofnitro-starch and from 25% to 40% of a solution ofammonium nitrate inWater, said solution containing less' than 65% of ammonium] nitrate,substantially as described.

j WALTERQ. S LU TQ It is hereby certified that in Letters Patent No. 1,386,47 ,"g r ented August 2, 1921, upon the application of Walter O.Snellihg iffllento tr Pennsylvania, for an improvement in N itrostarchExplosiyes, a'n rrti eppears ihithe printed specificetion requiringcorrection as follows; Page 2, "not 'iine to 106, comprising presentclaim 10 and insert the following as 1Q- 10. An explosive consisting ofnitrosta rch substantially as described; 1 v

and that the said Letters Patent should be'withlthrs orrectior rtherein.that the same may conform to the record of the 1- Signed and sealed this11th day of October 1 [BEALJ I t i v WM. re 31mm,

Actintrj gpmmifissiibner of Patents.

It is hereby certified that in Letters Patent No. 1,386,437, grantedAugust 2, 1921, upon the application of Walter O. Snelling, ofAllentown,Pennsylvania, for an improvement in Nitrostarch Explosives, anerror appears in the printed specification requiring correction asfollows: Page 2, strike out lines 104 to 106, comprising present claim10 and insert the following as claim 10: g

10. An explosive consisting of nitrostarch containing more than 10% ofwater,

substantially as described. and that the said Letters Patent should beread with this correction therein that the same may conform to therecord of the case in the Patent Oflice.

Signed and sealed this 11th day of October A. 1) 1921.

[sEAn] WM. A. KINNAN,

Acting Commissioner of Patents.

